Conversation with Uhnder CEO: 4D imaging radar has a cost advantage over lidar at the L2+ stage

4D imaging radar may revolutionize car perception!

A few days ago, Weilai announced the adoption of NXP’s 4D imaging radar solution. Tesla earlier reported that it would use Arbe’s 4D imaging radar.

The popularity of 4D imaging radar continues to rise! According to statistics from Chexixi, at least six domestic 4D imaging radar companies have received financing since 2023, with a total amount of billions of yuan. A new tens-billion track is being born!

The performance of 4D imaging radar has greatly improved, and the cost is only one-fifth of lidar, which has become the main reason for the increase in popularity.

After delving into the technology types of 4D imaging radar, Chexixi found that digital code modulation (DCM), a communication technology widely used in mobile phones, is moving toward civilian vehicles, and traditional millimeter wave radar is moving from the analog signal era to the digital encoding era.

So why can 4D imaging radar achieve such results? What are the principles and routes behind it? Can it really replace lidar? Chexixi found the answer after interviewing well-known companies in the industry, investigating market conditions, and studying technical principles.

1. The surge in popularity of 4D imaging radar has set off a new round of financing.

Recently, Dutch computer chip manufacturer NXP Semiconductors announced that NIO will use its 4D imaging radar solution. Earlier this year, the Tesla HW4.0 computer board was exposed. Combined with the 4D millimeter wave radar documents previously submitted by Tesla to the FCC, the new Ethernet interface may be connected to the 4D millimeter wave radar.

For a time, the popularity of 4D imaging radar has greatly increased, and many institutions have expressed their optimism about the development of 4D imaging radar in the Chinese market and have made positive future expectations for this.

Among them, the Gaogong Intelligent Automobile Research Institute predicts that the number of front-mounted 4D imaging radars in China's passenger car market will exceed one million in 2023, and that by 2025, the proportion of 4D imaging radars in all forward millimeter wave radars is expected to exceed 40%.

According to calculations by Yiou Think Tank, China's vehicle-mounted 4D imaging radar market will reach US$300-400 million (approximately RMB 2.1-2.8 billion) in 2025.

CICC also gave the expected growth rate of the radar market. From 2022 to 2025, the average annual compound growth rate of the domestic 4D imaging radar market will be 34%, 64% and 88% respectively.

Such a huge and rapidly growing domestic market has also driven the rapid development of related radar companies. Some time ago, 4D imaging radar company Sion led the way in completing hundreds of millions of yuan in Series A financing, led by Xiaomi and NIO. According to incomplete statistics from Chexi, at least six domestic 4D millimeter-wave radar companies have received financing since 2023, with a total amount of billions of yuan.

Financing status of Chinese millimeter wave radar companies in 2023

In addition, foreign companies are also very optimistic about the domestic market potential and attach great importance to the Chinese market. This year’s Shanghai Auto Show has attracted many foreign 4D imaging radar-related companies to participate in the exhibition.

Manju Hegde, co-founder and CEO of Uhnder, an American digital radar chip company, said in an interview with reporters during the Shanghai Auto Show: "The Chinese market is developing very fast, and the enthusiasm for 4D digital imaging radar is also very high. The Shanghai Auto Show is a very important opportunity. , we will take this opportunity to contact and visit many important customers to help them achieve large-scale mass production as soon as possible. In the future, we will often come to participate in activities and communicate with customers, partners, and industry experts.”

2. The performance jump of 4D imaging radar drives changes in automotive perception

Multi-sensor fusion is the main route adopted by current smart cars, and the cost of lidar has been difficult to effectively reduce. Therefore, cameras and millimeter-wave radar have become the main participants in sensor fusion perception. As a type of millimeter-wave radar, 4D imaging radar has greatly improved its performance and its cost performance is still excellent. This has made 4D imaging radar increasingly popular recently.

The target detection information of traditional 3D millimeter wave radar is the distance between the radar and the target, relative radial velocity, and horizontal angle data. It faces problems such as no height testing capability, low angular resolution, and low static object awareness. When encountering a stationary vehicle, target information is easily mixed with ground clutter, making identification difficult.

On the basis of the horizontal antenna of the 3D millimeter wave radar, the 4D millimeter wave radar adds a transmitting and receiving antenna arranged in the vertical direction, thereby increasing the estimation of the target height. Compared with 3D millimeter wave radar, it has the characteristics of large number of antennas and high density, and the output point cloud image density is higher. There have been improvements in distance resolution, distance accuracy, angle resolution, angle accuracy, speed resolution and speed accuracy.

4D millimeter wave radar detection range

Currently, 4D imaging radars are divided into two technical routes, frequency modulated continuous wave (FMCW) and phase modulated continuous wave (PMCW), based on different ways of radiating electromagnetic waves. These two routes are implemented based on different modulation methods.

In radar, the channel cannot directly transmit the original signal generated by the source. The signal generated by the source needs to be transformed into a suitable signal before it can be transmitted in the channel. The process of converting the signal generated by the source into a signal suitable for channel transmission is called modulation.

Use analog signals to control changes in carrier parameters. This modulation method is called analog modulation, which is currently the most widely used. Use data signals to control changes in parameters of carrier signals. This modulation method is called digital modulation, and digital modulation is becoming a new trend. . From this perspective, radar can also be divided into analog radar and digital radar.

Currently, in the field of 4D imaging radar, the Frequency Modulated Continuous Wave (FMCW) scheme based on analog modulation is the main one. The main representative is the Israeli company Arbe. The radar signal processing of this scheme is mainly completed in analog circuits.

Millimeter wave radar working system (picture source network)

The phase-modulated continuous wave solution based on digital code modulation (DCM) technology is gradually being used in the field of 4D imaging radar as technology costs decrease. This solution uses multiple antennas to simultaneously transmit quadrature phase encoding signals to detect the distance and speed of the target.

Radar chips using DCM technology mainly process radar signals digitally and allow the use of algorithms on the radar for more advanced digital processing. Its representative radar chip company is Uhnder of the United States. For example, Uhnder's 4D digital radar chip S80 is completely software-defined, with a built-in processor that can run algorithms on the chip and can also be optimized using advanced deep learning neural networks and AI (artificial intelligence).

At the same time, the phase-modulated continuous wave solution based on digital code modulation (DCM) technology can not only detect longer distances, but also can effectively detect targets while effectively resisting radar and radar interference compared to traditional analog frequency-modulated continuous wave (FMCW) radars. Mutual interference between radars.

Taking products based on Uhnder 4D digital radar chip S80 as an example, Uhnder CEO and co-founder Manju Hegde said: "Compared with existing analog radars, the resolution of digital radars has increased by 16 times, and the target reflection power has increased by 24 times. times, the contrast is increased by 30 times.”

Uhnder 4D digital radar chip S80

In terms of cost, 4D imaging radar also shows great advantages over lidar. Compared with traditional 3D millimeter wave radar, Manju Hegde also said: "Compared with analog radar, digital radar can bring dozens of times the cost. Performance improvement. However, if analog radar wants to achieve the same performance, no matter what method is used, the price will definitely be very high. By using Uhnder digital radar solutions, manufacturers can achieve greater performance within the same price range. promote."

In other words, the current cost of 4D imaging radar has significantly jumped compared to the performance of traditional 3D millimeter wave radar, while the cost has increased slightly. It can even surpass lidar in some aspects of performance, but the cost is much lower than lidar.

3. Uhnder CEO: 4D imaging radar can partially replace lidar

Compared with lidar, 4D imaging radar is less susceptible to rain, snow, and haze weather, and its reliability and durability will be better. At the same time, 4D imaging radar, as an upgraded version of 3D millimeter wave radar, costs only one-fifth of lidar.

4D imaging radar significantly surpasses traditional 3D millimeter-wave radar in performance. Although there is still a gap between 4D imaging radar and lidar, its low cost compared to lidar makes it very attractive.

According to the Israeli company Arbe, the price of 4D imaging radar is expected to be between US$100-150 (approximately RMB 700~1,000 yuan). The cost is only one-fifth of lidar.

Comparison of key parameters of vehicle sensing hardware

In this context, for a time, there were more and more discussions about the relationship between 4D imaging radar and lidar. Can 4D imaging radar really replace lidar?